Automatic switch.



M. MINTZ.

AUTOMATIC SWITCH.

APPLICATION FILED FEB.Z4.19H.

1, 182,399. Patented May 9, 1916.

2 SHEETSSHEET I.

JE J e/YZ JE' Mia/ THE/COLUMBIA PLANOGRAPH co, WASHINGTON, D. c.

Patented May 9, 1916.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

MIKE MINTZ, OF ROCK ISLAND, ILLINOIS, ASSIGNOR TO GEARLESS AUTOMATICPUMP COMPANY, OF ROCK ISLAND, ILLINOIS, A CORPORATION OF ILLINOIS.

AUTOMATIC SWITCH.

Application filed February 24, 1911.

Z '0 all to 7mm it may concern Be it known that I, MIKE MINTZ, a citizenof the United States, residing at Rock Island, in the county of RockIsland and State of Illinois, have invented new and useful Improvementsin Automatic Switches, of which the following is a full, clear, concise,and exact description, reference being had to the accompanying drawing,forming a part of this specification.

My invention relates to automatic switches, designed to open and closean electrical circuit, and has for its object the production of a devicethat will give substantially absolute accuracy of contact.

Further objects are the provisions of improved details of construction,whereby the contact may be maintained,

A further object is the production of a device embodying greatsimplicity of construction, that may be cheaply made and one that is notliable to get out of order.

These and such other objects as may hereinafter appear, are attained bymy device, embodiments of which. are illustrated in the accompanyingdrawings, in which Figure 1 represents an end elevation of my improveddevice with the front plate of the switch casing removed. Fig. 2represents afront view of the switch casing with the front plateremoved; Fig. 3 represents a sectional view 011 the line 33 of Fig. 2,looking in the direction indicated by the arrows; Fig. 4 represents anend view of the contact yoke or fork; Fig. 5 represents a perspectiveview of the means for operating the oil relief valve lever. Fig. 6represents a side elevation of the mercury container with the frontplate removed; Fig. 7 represents a sectional View on the line 1111 ofFig. 6, looking in the direction indicated by the arrows; Fig. 8represents a sectional view on the line 1212 of Fig. 6 looking in thedirection indicated by the arrows.

Like numerals of reference indicate like objects of the several figuresof the drawings.

Referring now to the drawings, 13 represents a suitable electric motorcase, resting on a base 14 and containing a suitable motor. On theopposite ends of the motor shaft 20 outside the case are mounted crankpins 21 to which are secured pistons 22 of the pumps. The compressed airis forced through suitable valves and pipes into the Specification ofLetters Patent.

Patented May 9, 1916.

Serial No. 610,644.

lower diaphragm chamber of the diaphragm valve casing 27. The air thenpasses through a pipe 28 1nto any suitable air tank .or receptacle 29.Connecting with the upper diaphragm chamber of the casing 27, is a pipe30, having an end connection 31 screwed into a suitable casing 32,mounted on the motor casing. Screwed on to the top of this casing and inopen communication with the chamber 33 is a diaphragm casing comprisinga lower shell 3%, and an upper shell 35 screwed or secured thereto. Aflexible diaphragm 36, the edges of which are preferably held betweenthe upper and lower shells, actuates a stem the end or seat 40 of whichextends into the switch casing.

It is evident from the above that as the chamber below the diaphragm isin open connection with the upper chamber of the diaphragm valve and thecompressed air tank, the pressure in the chamber will be the same asthat in the tank and when the pressure in said tank is suiiicient toraise the stem, it will remain in a raised position until the pressurein the tank falls below a predetermined point, when the stem will drop.

A switch casing comprising preferably a cylindrical shell or box 41 witha suitable cover 42 is rigidly mounted on the top of the diaphragmcasing 27 by means of suitable castings 43. A socket 44 is secured tothe inside, preferably at the center of the back plate and a shaft orjournal 15 is mounted therein passing through the casing and through anopening in the cover 42 and adapted to be engaged by a thumb nut 46,serving to hold the cover rigidly in place as well as insuring therigidity of the shaft 45.

The circumferential shell 47 is cut away at 48, and a porcelainmercury-containing block A mounted therein and held rigidly in place bymeans of a clamping member comprising a bent strip of metal, one end 49of which is screwed to the back of the casing and the other end 50 benta little less than 90 degrees and engaging the side of the block, theinterior angle between the sides of the bent strip being a little over90 degrees. It is thus apparent that by screwing down the sides 49 theside 50 is brought tightly against the side of the block, locking itsecurely in place. This block is made wedge shaped and cut away at 5152to fit within the opening in the circumferential wall of the casing andforming the shoulders 53 bearing against the inner face of the casino. 7V

In order to remove the block, it is simply necessary to loosen the screw5% which will permit the block to be slipped out of place and the factthat it is made wedge shaped insures great rigidity, even though theshoulders abovereferred to are omitted.

Referring now to theblock itself, this is preferably formed fromporcelain or some other insulating material and is provided with a pairof cups or depressions 55, placed side by side and having raised flangesor rims 56. This feature prevents the mercury from over-flowing from onecup into the other cup or from short circuiting the device. Screwopenings extend through the block from near the bottom of each cup tothe outside and in these openings suitable contact screws or pins 57 aremounted terminating in contact buttons 58 within the cup. The blockis'formed with enlarged openings 59 surrounding the screw openings andalso with channels 60 leading therefrom,'

thus permitting the insertion of the binding nuts 61 and connectmg wires62. These wires are held in place by means of screw nuts 94. The outerface of'the block is formed with depressions 63 adapted to receivecorresponding bosses or lugs 64 on the face of the covering plate 65which is adapted to fit over the outer face of the block and protect andinsulate the binding posts and connections. This cover is held in placeby means of a suitable bolt 66 passing through the block and is heldremovably in place by means of a thumb nut 67, thus making all of theconnections accessible from without by simply removing the plate 65.

In order to prevent too great an amount of mercury within the cups, Iprovide the openings 68 in each cup, a definite distance from the bottomso that any excess of mercury will drain off and give the known depth ofmercury within the cups. I provide an opening 96 in the bottom of thecasing so that any mercury that may overflow while the cups are beingfilled or at any other time, can at once escape, thus avoiding alldangers of short circuiting.

Loosely mounted on shaft a5 is a segmental arm 70 provided with aweighted end 71 and a pair of stays or lugs 7273 spaced apart on saidarm, a definite distance from each other. On the other end of this armis mounted an insulating block 74 in the end of which is mounted a.metallic yoke or fork B comprising cross bar 75 and downwardlyprojecting pins 76 and 76 Swingingly mounted on the shaft 45 and besidethe arm 7 O is an arm 7 7 provided with a. weighted end 78. The lowerend of the arm extends below the shaft and terminates in the fork oryoke members 7 97 9 This arm is close to the segmental arm 70 and ispositioned between lugs 7:273 and adapted to engage lug 72 and force thepins of the fork within the cups when it is desired to close the circuitand to force the arm backwardly and the pins out of the cups, when it isdesired to break the circuit. The movement of this arm is accomplishedin the following manner :-Pivotally mounted at 80 within the casing is alever 81 extending outside the casing and adapted to support a weight82; an upwardly extending arm 83 is mounted near the end of the lever $1at 84; and bent over at its end 85, said in extending between the yokemember 979 The top d0 of the stem engages the bottom of the leverslbetween its pivotal point and its lowerend, forming a fulcrumtherefor, thus providing means for shifting the position of the leverand also the weighted arm 77. A bell crank lever 87 is pivotally mountedon a pin 86 outside of the casing, one arm 87 extending within theswitch casing and in position to be engaged by pin 88 extendingrearwardly from the end of the lever 81. The other arm 87 of the bellcrank lever extends downwardly and its end 87 is adapted to control thevalve 89 for carrying off surplus oil opening into an oil. receptacle90.

My device is illustrated in connection with a. system used in the saleof liquors in which compressed air is utilized to force the liquor fromfaucets. The device may be used in many other arts, for instance, indentists and photographers shops, etc, or in fact. in any place wherecompressed air is used.

It is well known that in the use of compressed air it is quiteessential" that the pressure within the storage tank should not beallowed to fall below a predetermined point. This is regulated by theautomatic switch mechanism in the following manner: The required degreeof maximum pressure being determined upon, the weight 82 on the arm 81,is moved to such a distance as to require an exertion of the desiredpressure exercised through the diaphragm 36 and stem 38 to raise thelever and open the switch. The switch will remain open until thepressure falls to the predetermined point when the action of the weightwill again close the switch and start the motor.

Referring now more particularly to the operation of my device, let ussuppose the current to be on and the motor operating the prunps, theparts of the switch being in the position indicated in full lines in 2and the circuit being closed through the mercury in the cups and thefork. Compressed air is forced through the pipe 28 into the tank orreceptacle at the same time a like pressure is transmitted to thechamber below the switch releasing diaphragm and when this pressurereaches a predetermined point the stem 40 raises the lever 81 and rocksthe arm 77. As soon as the ball 7 8 passes the vertical plane of theshaft 45, the arm falls and strikes against the pin 73 and rocks thesegmental arm into the position shown by dotted lines in Fig. 2,withdrawing the fork from the mercury and breaking the electricalcircuit through which the motor is operated, thereby stopping the motor.The compressed air is then used from the tank until such a time as thepressure within the tank falls below the predetermined point and whenthe pressure below the diaphragm reaches such a point, the weight 82forces the lever 81 down and carries the weighted arm forwardly until itfalls against the pin 72 and rocks the segmental arm forwardly and carries the fork again into the mercury reestablishing the electricalcircuit not shown and starting the motor, thus completing a cycle. Itwill be noted that the lever 81 at the time that it operates to breakthe circuit opens the relief valve 89 thereby reducing the pressurewithin the lower diaphragm chamber 26 below the diaphragm 92 as shown inFigs. 3, 5 and 7.

By the use of the porcelain block with the cups therein for containingthe mercury, I provide for positive insulation and by the use of theover-flow holes I produce a positive minimum breaking distance betweenthe fork and the mercury.

Attention is also called to the method of securing the wires asillustrated in Figs. 6 and 7 in which the nut 9% is first screwed firmlyin place, making it possible to remove the wire from the terminalwithout disturbing the mercury in the cups.

The cover or front plate 42 is preferably cast with a plurality ofinwardly branching lugs 95 adapted to bear against the inner peripheryof the casing, thus insuring a tight fit when the nut 4L6 is screwed inplace.

Other details of construction are of course possible instead of thoseillustrated in the drawings w iich are not departures from the spirit ofmy invention.

I claim:

1. In a device of the class described, the combination with a circularcasing, a mercury container mounted therein, said container comprising ablack of insulating material having cups integral therewith and adaptedto bear against one side of said casing, raised flanges surrounding thetops of said cups above the level of the mercury, a movable membermounted to swing within said casing, a contact fork mounted on saidmember and insulated therefrom, and means for causing said fork to swinginto and out of said cups.

2. In a device of the class described, the combination with a circularcasing, a mercury container mounted therein, said container comprising ablock of insulating material having cups integral therewith providedwith over-flow openings and adapted to bear against one side of saidcasing, raised flanges surrounding the tops of said cups above saidoverflow openings, a mov able member mounted to swing within saidcasing, a contact fork mounted on said member and insulated therefrom,and means for causing said fork to swing into and out of said cups.

3. In a device of the class described, the combination with a circularcasing, a mer cury container mounted therein, said container comprisinga wedge-shaped block of insulating material having cups integraltherewith and adapted to bear against one side of said casing, a movablemember mounted to swing within said casing, a contact fork mounted onsaid member and insulated therefrom, means for causing said fork toswing into and out of said cups, permanent contacts from the bottom ofsaid cups to the back of said block, a portion of the casing being cutaway at the rear of said block, and an insulating plate removablymounted on said block covering said contacts.

4. In a device of the class described, the combination with a circularcasing, a wedgeshaped mercury container mounted therein and adapted tobear against one side of said casing, said container comprising a blockof insulating material having a pair of cups integral therewith providedwith overflow openings, raised flanges surrounding the tops of said cupsabove said overflow openings, a movable member mounted to swing withinsaid casing, a contact fork mounted on saic. member and insulatedtherefrom, means for causing said fork to swing into and out of saidcups, permanent contacts from the bottom of said cups to the back ofsaid block, a portion of the casing being cut away at the rear of saidblock, and an insulating plate reinovably mounted on said block coveringsaid contacts.

In witness whereof, I have hereunto sub scribed my name in the presenceof two witnesses.

MIKE MINTZ.

copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

